Correlation of patient reported outcome measures with endoscopic findings in pediatric chronic adenoiditis and chronic rhinosinusitis.

BACKGROUND: Studies in adult chronic rhinosinusitis (CRS) showed poor correlation between patient reported outcome measures (PROMs) and objective findings. Our goal is to study the correlation between the sinus and nasal quality of life (SN-5) and the 22-items sinonasal outcome test (SNOT-22) surveys with endoscopy findings in children with chronic adenoiditis (CA) and CRS. METHODS: Cross-sectional study of all pediatric patients (age 2-18) presenting for CA or CRS was performed. Patients and caregivers were asked to fill the SN-5 and SNOT-22 questionnaires at initial and follow up visits. Demographics and comorbidities were collected. Objective findings included endoscopy Modified Lund-Kennedy (MLK) scores and adenoid tissue size. RESULTS: 124 children were included, with mean age of 9.9 years (SD = 4.8) and 46.8% female. 36.3% had allergic rhinitis, 23.4% had asthma, and 4% had obstructive sleep apnea. Moderate correlation was found between the rhinologic domain of SNOT-22 and MLK scores (r = 0.36, p = 0.001) and between SN5 scores and adenoid size in all patients (r = 0.39, p < 0.001). SNOT-22 scores showed moderate correlation with adenoid size (r = 0.42, p < 0.001) more specifically in CA patients (r = 0.54, p < 0.001). The correlation of SN5 and MLK scores were higher in children with allergic rhinitis or asthma. The correlation between SN5 and adenoid size was lower in children with allergic rhinitis or asthma. CONCLUSION: There is discrepancy between the subjective measures and the objective findings in children with CA or CRS. The physical exam findings may not reflect the effect of CRS on the quality of life of children.

[Correlation study of NCF2 in chronic rhinosinusitis with nasal polyps].

Objective:After selecting NCF2 based on bioinformatics, clinical experiments were conducted to verify the expression of NCF2 in chronic rhinosinusitis with nasal polyps to study its correlation. Methods:The differentially expressed genes（DEGs） between CRSwNP and non-CRS patients were explored using the CRS-related dataset from the gene expression omnibus GEO database. The weighted gene co-expression network（WGCNA） was used for cluster analysis. The expression and cell distribution of NCF2 in the tissues were determined by single gene enrichment analysis（GSEA）, immune inflammatory infiltration analysis, and principal component（PCA） analysis. The expression degree of NCF2 in the tissues of the subjects was determined by immunohistochemistry, and the percentage of EOS in the peripheral blood of the subjects was detected and the correlation was analyzed. EOS in the tissues of the subjects were counted under a microscope and compared. Results:①The Venn diagram was obtained by crossing the module with the highest correlation between DEGs and WGCNA to determine the core gene NCF2. ②GSEA analysis showed that NCF2 was significantly related to the immunological processes such as allogeneic rejection and asthma. ③The area under the ROC curve was 1, indicating that NCF2 had diagnostic value for CRSwNP. ④NCF2 was highly expressed in nasal polyps, mainly distributed in monocytes and eosinophils. ⑤HE staining showed that the number of EOS in ECRSwNP tissues and the percentage of eosinophils in peripheral blood were higher than those in nonECRSwNP and control groups. ⑥The immunohistochemistry results showed that NCF2 was significantly expressed in the nasal polyps of ECRSwNP patients, which was higher than that in the nasal mucosa of nonECRSwNP group and control group. ⑦The expression of NCF2 in tissues was positively correlated with EOS count in ECRSwNP group and EOS expression in peripheral blood. Conclusion:The expression of NCF2 is increased in eosinophilic chronic rhinosinusitis with nasal polyps, and it is significantly correlated with the expression of eosinophils in peripheral blood and tissues, suggesting that NCF2 may be used as a basis for the intrinsic classification of ECRSwNP and a reference index for clinical diagnosis and treatment.

[The auxiliary diagnostic value of ECP and MPO expression in nasal secretions in different types of rhinitis].

Objective:To evaluate the expression of eosinophil cationic protein and myeloperoxidase in nasal secretions in different types of rhinitis, and to explore their values in the differential diagnosis of different types of rhinitis. Methods:Six hundred and eighty-four subjects were selected, including 62 subjects in the acute rhinitis group, 378 subjects in the allergic rhinitis group, 94 subjects in the vasomotor rhinitis group, 70 subjects in the eosinophilic non-allergic rhinitis group, and 80 subjects in the control group. Nasal secretion samples were collected from the five groups, and the percentages of inflammatory cells were counted by Rachel's staining, and the expression of ECP/MPO was detected by colloidal gold assay. The correlation between the clinical diagnosis, the inflammatory cells in the nasal secretions and the expression of ECP/MPO was analyzed. Results:Nasal cytological smears showed that compared with the control group, the percentage of eosinophils in the AR and NARES groups were significantly higher （P<0.05）, while the percentage of neutrophils was not different （P>0.05）; the percentage of neutrophils was significantly higher in the acute rhinitis group compared with the control group （P<0.05）, while the percentage of eosinophils was not statistically different （P>0.05）; in vasomotor rhinitis group, the eosinophils and neutrophils were not statistically different compared with the control group（P> 0.05）. The colloidal gold results showed that there were differences in the expression of ECP/MPO in different types of rhinitis, among which 49 cases （79.0%） in the acute rhinitis group expressed ECP+/MPO+; 267 cases （70.6%） in the AR group and 56 cases （75.7%） in the NARES group expressed ECP+/MPO-; 80 cases （85.1%） in the vasomotor rhinitis group and 69 cases （86.3%） in the control group expressed ECP-/MPO-. Conclusion:The differences in ECP and MPO expression between different types of rhinitis have certain reference value for the differential diagnosis of different types of rhinitis and the selection of treatment programs.

Surgical and medical management of chronic rhinosinusitis in pediatric cystic fibrosis patients: Impact on olfactory symptoms.

BACKGROUND AND PURPOSE: Olfactory dysfunction (OD) commonly occurs in patients with sinonasal dysfunction, but the prevalence and severity of olfactory issues in adolescents with cystic fibrosis (AwCF) is unclear. OD may contribute to dietary deficiencies and exacerbate nutritional challenges. We sought to review literature on the effectiveness of medical and surgical management of sinonasal symptoms in AwCF and the associated impact on olfactory function. METHODS: We performed a systematic literature search of PubMed, Embase, Web of Science, and Ebsco CINAHL from 1980 to 2022 per PRISMA-ScR protocols to conduct a scoping review in an effort to compile data on study design, patient demographics, clinical characteristics and outcomes, along with risk of bias. RESULTS: Of 368 abstracts, 3 articles exclusively evaluated AwCF for a total of 34 patients. Two studies evaluated endoscopic sinus surgery (ESS) and dornase alfa. An additional 6 articles were included for mixed pediatric and adult CF populations totaling 313 patients. Interventions included ESS, elexacaftor-tezacaftor-ivacaftor (ETI), ivacaftor, saline, dornase alfa, hyaluronic acid, and hyaluronic acid-tobramycin combination. Outcome measures included subjective assessment of OD using non-validated (4/9) and validated (4/9) surveys, and psychophysical (1/9) smell testing. Studies evaluating ESS, FESS, dornase alfa, ivacaftor, and both hypertonic and isotonic saline reported statistically significant improvement in OD, whereas ETI failed to improve OD despite improvement in other quality of life measures. CONCLUSIONS: There is limited data regarding the impact of medical and surgical interventions on olfaction for AwCF. Assessment of olfaction was often limited to subjective and qualitative self-report. We suggest that tracking of olfactory outcomes with psychophysical testing is critical in this population with dietary challenges and weight management issues.

The cyclooxygenase-2 upregulation mediates production of PGE2 autacoid to positively regulate interleukin-6 secretion in chronic rhinosinusitis with nasal polyps and polyp-derived fibroblasts.

Chronic rhinosinusitis (CRS) can be traditionally classified as CRSwNP [with nasal polyps (NPs)] and CRSsNP (without NPs) based on the clinical phenotypes but recently suggested to be classified by the endotypes. We have identified overexpression of the cyclooxygenase-2 (COX-2) gene in NP tissues of Taiwanese CRSwNP patients. Therefore, in this study, we sought to investigate its protein expression/location/distribution in NP specimens and explore its roles in nasal polyposis. The COX-2 protein and mRNA expression was found higher in NPs than that in the control and CRSsNP patients' nasal tissues, mainly located at the epithelium and subepithelial stroma. Consistently, the CRS-related peptidoglycan (PGN) and bradykinin provoked COX-2 mRNA and protein upregulation in the human NP-derived fibroblasts and caused PGE2, thromboxane A2 (TXA2), and interleukin (IL-6) secretion in culture medium. Further analysis revealed that the PI3K/Akt activation and COX-2 induction were necessarily required for PGN-induced IL-6 production/secretion and the induced PGE2, but not TXA2, was speculated to affect IL-6 protein trafficking and production. Finally, the IL-6 increase observed in vitro could also be detected in NP tissues. Collectively, we demonstrated here that COX-2 protein and IL-6 are overexpressed in human NP tissues. In response to PGN challenge, the PI3K/Akt activation and COX-2-mediated PGE2 autacoid correlates with extracellular IL-6 protein trafficking/production in NP-derived fibroblasts, which can additionally contribute to the production of Th17-related cytokines such as IL-17 and TNF-α. This study also suggests COX-2 as a special biomarker for CRSwNP endotyping and may highlight the importance of COX-2 inhibitors in treating CRSwNP.

Chronic Rhinosinusitis-Microbiological Etiology, Potential Genetic Markers, and Diagnosis.

Chronic rhinosinusitis (CRS) is a significant public health problem. Bacterial colonization and impaired mucociliary clearance play a significant role in the inflammatory process. Several inflammatory pathways and host defense elements are altered in CRS, which may contribute to observed differences in the microbiome. To date, researching CRS has been difficult due to limited access to the studied tissue and a lack of available biomarkers. Ongoing scientific research is increasingly based on simple and objective analytical methods, including sensors, detection with PCR, and sequencing. Future research on microbiota and human factors should also include genomics, transcriptomics, and metabolomics approaches. This report analyzes the changes that occur in the paranasal sinuses of people with acute and chronic rhinosinusitis, the composition of the microbiota, the human genetic markers that may shed light on the predisposition to CRS, and the advantages and disadvantages of classical and molecular diagnostic methods, as well as addressing the difficulties of sinusitis treatment.

A Novel Model of Staphylococcus aureus-Induced Lymphoplasmacytic Rhinosinusitis in Rats.

Chronic rhinosinusitis (CRS) is characterized by sinonasal mucosal inflammation. Staphylococcus aureus (S. aureus) is associated with severe CRS phenotypes. Different animal models have been proposed to study the association of CRS and S. aureus. However, current animal models are expensive due to the use of large animals, have high barriers to ethics approval, or require invasive surgical intervention, necessitating a need for a model that can overcome these limitations. This study aimed at establishing a reliable and efficient rat lymphoplasmacytic inflammatory model for rhinosinusitis. Sprague Dawley rats received a daily intranasal application of 20 µL of saline, S. aureus CI-182 exoprotein (250 µg/mL), or exoprotein CI-182 in combination with S. aureus clinical isolate (CI-908 or CI-913) 108 colony-forming unit (CFU)/mL. The rats' sinuses were harvested at 1 and 2 weeks post-intervention. The CFU and histopathologic examination of inflammation were evaluated. S. aureus clinical isolates CI-908 or CI-913 in combination with the exoprotein (CI-182) had higher CFUs and caused persistently higher inflammation at both the 1 and 2-week post-intervention compared to the exoprotein and saline group. The observed inflammatory cell type was lymphoplasmacytic. This study provided evidence that the combination of a S. aureus exoprotein with S. aureus induces inflammation that persists for a minimum of two weeks post-intervention. This model is the first known animal model to create the lymphoplasmacytic inflammation subtype seen in CRS patients. This offers a cost-effective, accessible, non-invasive, and easy-to-replicate model to study the causes and treatment of such inflammation.

SerpinB3/B4 Abates Epithelial Cell-Derived CXCL8/IL-8 Expression in Chronic Rhinosinusitis with Nasal Polyps.

Background: Serine proteinase inhibitors, clade B, member 3 (SerpinB3) and B4 are highly similar in amino acid sequences and associated with inflammation regulation. We investigated SerpinB3 and B4 expression and their roles in chronic rhinosinusitis with nasal polyps (CRSwNP). Methods: The expression of SerpinB3 and B4 in nasal mucosa tissues, brush cells, and secretions from CRSwNP patients was measured, and their regulation by inflammatory cytokines were investigated. Their functions were also analyzed using air-liquid interface (ALI)-cultured primary human nasal epithelial cells (HNECs) and transcriptomic analysis. Results: Both SerpinB3 and B4 expression was higher in nasal mucosa, brush cells, and secretions from eosinophilic (E) CRSwNP and nonECRSwNP patients than in healthy controls. Immunofluorescence staining indicated that SerpinB3 and B4 were primarily expressed in epithelial cells and their expression was higher in CRSwNP patients. SerpinB3 and B4 expression was upregulated by interleukin-4 (IL-4), IL-5, IL-6, and IL-17a. Transcriptomic analysis identified differentially expressed genes (DEGs) in response to recombinant SerpinB3 and B4 stimulation. Both the DEGs of SerpinB3 and B4 were associated with disease genes of nasal polyps and inflammation in DisGeNET database. Pathway enrichment indicated that downregulated DEGs of SerpinB3 and B4 were both enriched in cytokine-cytokine receptor interactions, with CXCL8 as the hub gene in the protein-protein interaction networks. Furthermore, CXCL8/IL-8 expression was downregulated by recombinant SerpinB3 and B4 protein in ALI-cultured HNECs, and upregulated when knockdown of SerpinB3/B4. Conclusion: SerpinB3/B4 expression is upregulated in nasal mucosa of CRSwNP patients. SerpinB3/B4 may play an anti-inflammatory role in CRSwNP by inhibiting the expression of epithelial cell-derived CXCL8/IL-8.

Type 2 and Non-type 2 Inflammation in the Upper Airways: Cellular and Molecular Alterations in Olfactory Neuroepithelium Cell Populations.

PURPOSE OF REVIEW: Neurogenesis occurring in the olfactory epithelium is critical to continuously replace olfactory neurons to maintain olfactory function, but is impaired during chronic type 2 and non-type 2 inflammation of the upper airways. In this review, we describe the neurobiology of olfaction and the olfactory alterations in chronic rhinosinusitis with nasal polyps (type 2 inflammation) and post-viral acute rhinosinusitis (non-type 2 inflammation), highlighting the role of immune response attenuating olfactory neurogenesis as a possibly mechanism for the loss of smell in these diseases. RECENT FINDINGS: Several studies have provided relevant insights into the role of basal stem cells as direct participants in the progression of chronic inflammation identifying a functional switch away from a neuro-regenerative phenotype to one contributing to immune defense, a process that induces a deficient replacement of olfactory neurons. The interaction between olfactory stem cells and immune system might critically underlie ongoing loss of smell in type 2 and non-type 2 inflammatory upper airway diseases. In this review, we describe the neurobiology of olfaction and the olfactory alterations in type 2 and non-type 2 inflammatory upper airway diseases, highlighting the role of immune response attenuating olfactory neurogenesis, as a possibly mechanism for the lack of loss of smell recovery.

CD4+ Foxp3+ Regulatory T-cells in Modulating Inflammatory Microenvironment in Chronic Rhinosinusitis with Nasal Polyps: Progress and Future Prospect.

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a subtype of chronic rhinosinusitis (CRS) characterized by the presence of nasal polyps (NP) in the paranasal mucosa. Despite the complex etiology, NP is believed to result from chronic inflammation. The long-term aftermath of the type 2 response is responsible for symptoms seen in NP patients, i.e. rhinorrhea, hyposmia, and nasal obstruction. Immune cellular tolerogenic mechanisms, particularly CD4 + Foxp3 + regulatory T cells (Tregs), are crucial to curtail inflammatory responses. Current evidence suggests impaired Treg activity is the main reason underlying the compromise of self-tolerance, contributing to the onset of CRSwNP. There is compelling evidence that tumor necrosis factor 2 (TNFR2) is preferentially expressed by Tregs, and TNFR2 is able to identify the most potent suppressive subset of Tregs. Tumor necrosis factor (TNF)-TNFR2 interaction plays a decisive role in the activation and expansion of Tregs. This review summarizes current understanding of Tregs biology, focusing on the discussion of the recent advances in the study of TNF-TNFR2 axis in the upregulation of Treg function as a negative feedback mechanism in the control of chronic inflammation. The role of dysregulation of Tregs in the immunopathogenesis of CRSwNP will be analyzed. The future perspective on the harnessing Tregs-mediated self-tolerant mechanism in the management of CRSwNP will be introduced.

Deep immune profiling of chronic rhinosinusitis in allergic and non-allergic cohorts using mass cytometry.

Chronic rhinosinusitis (CRS) is a persistent nasal and paranasal sinus mucosa inflammation comprising two phenotypes, namely CRS with nasal polyps (CRSwNP) and without (CRSsNP). CRSwNP can be associated with asthma and hypersensitivity to non-steroidal anti-inflammatory drug (NSAID) in a syndrome known as NSAID-exacerbated respiratory disease (N-ERD). Furthermore, CRS frequently intertwines with respiratory allergies. This study investigated levels of 33 different nasal and serum cytokines and phenotypic characteristics of peripheral blood mononuclear cells (PBMCs) within cohorts of CRS patients (n = 24), additionally examining the influence of comorbid respiratory allergies by mass cytometry. N-ERD patients showed heightened type 2 nasal cytokine levels. Mass cytometry revealed increased activated naive B cell levels in CRSwNP and N-ERD, while resting naive B cells were higher in CRSsNP. Th2a cell levels were significantly elevated in allergic subjects, but not in CRS groups. In conclusion, there are distinct immunological features in PBMCs of CRS phenotypes and allergy.

Allergic Rhinitis: A Review.

Importance: Allergic rhinitis affects an estimated 15% of the US population (approximately 50 million individuals) and is associated with the presence of asthma, eczema, chronic or recurrent sinusitis, cough, and both tension and migraine headaches. Observations: Allergic rhinitis occurs when disruption of the epithelial barrier allows allergens to penetrate the mucosal epithelium of nasal passages, inducing a T-helper type 2 inflammatory response and production of allergen-specific IgE. Allergic rhinitis typically presents with symptoms of nasal congestion, rhinorrhea, postnasal drainage, sneezing, and itching of the eyes, nose, and throat. In an international study, the most common symptoms of allergic rhinitis were rhinorrhea (90.38%) and nasal congestion (94.23%). Patients with nonallergic rhinitis present primarily with nasal congestion and postnasal drainage frequently associated with sinus pressure, ear plugging, muffled sounds and pain, and eustachian tube dysfunction that is less responsive to nasal corticosteroids. Patients with seasonal allergic rhinitis typically have physical examination findings of edematous and pale turbinates. Patients with perennial allergic rhinitis typically have erythematous and inflamed turbinates with serous secretions that appear similar to other forms of chronic rhinitis at physical examination. Patients with nonallergic rhinitis have negative test results for specific IgE aeroallergens. Intermittent allergic rhinitis is defined as symptoms occurring less than 4 consecutive days/week or less than 4 consecutive weeks/year. Persistent allergic rhinitis is defined as symptoms occurring more often than 4 consecutive days/week and for more than 4 consecutive weeks/year. Patients with allergic rhinitis should avoid inciting allergens. In addition, first-line treatment for mild intermittent or mild persistent allergic rhinitis may include a second-generation H1 antihistamine (eg, cetirizine, fexofenadine, desloratadine, loratadine) or an intranasal antihistamine (eg, azelastine, olopatadine), whereas patients with persistent moderate to severe allergic rhinitis should be treated initially with an intranasal corticosteroid (eg, fluticasone, triamcinolone, budesonide, mometasone) either alone or in combination with an intranasal antihistamine. In contrast, first-line therapy for patients with nonallergic rhinitis consists of an intranasal antihistamine as monotherapy or in combination with an intranasal corticosteroid. Conclusions and Relevance: Allergic rhinitis is associated with symptoms of nasal congestion, sneezing, and itching of the eyes, nose, and throat. Patients with allergic rhinitis should be instructed to avoid inciting allergens. Therapies include second-generation H1 antihistamines (eg, cetirizine, fexofenadine, desloratadine, loratadine), intranasal antihistamines (eg, azelastine, olopatadine), and intranasal corticosteroids (eg, fluticasone, triamcinolone, budesonide, mometasone) and should be selected based on the severity and frequency of symptoms and patient preference.

Prevalence and predictors of depression and anxiety in patients with chronic rhinosinusitis: a systematic review and meta-analysis.

BACKGROUND: Chronic rhinosinusitis (CRS) is a persistent inflammation of the sinuses. As a result of long-term discomfort, patients may experience symptoms of common mental disorders such as anxiety and depression. This may affect the quality of life and disease progression. However, there is still uncertainty about the extent of the problem. OBJECTIVE: This meta-analysis aimed to determine the prevalence of depression and anxiety symptoms in patients with CRS. SEARCH STRATEGY: We searched PubMed, Embase, Web of Science, Cochrane Library, and CBM databases for relevant studies published before 15 July 2022 in patients with CRS with concomitant depression and anxiety symptoms. DATA COLLECTION AND ANALYSIS: Two authors independently performed screening and quality assessment using validated tools. Extraction of data using predefined standardised data collection spreadsheets. Heterogeneity and inconsistency were checked using the I² statistic. RESULTS: The meta-analysis included 32 articles involving 56 933 patients. The prevalence of depression and anxiety symptoms was estimated at 24.7% (95% CI, 21.3% to 28. 1%) and 29.7% (95% CI, 19.3% to 40.2%). Subgroup analysis revealed the following: (1) CRS without nasal polyps (CRSsNP): 26.2% (95% CI, 21.9% to 30.5%), CRS with nasal polyps(CRSwNP): 20% (95% CI, 15.9% to 24%); (2) Female patients: 36. 1% (95% CI, 25.3% to 46.9%), male patients: 24.3% (95% CI, 12. 1% to 36.6%); and (3) The average age≤50 years patients: 29.8% (95% CI, 21.3% to 38.2%), the average age>50 years patients: 22. 1% (95% CI, 17.1% to 27%). CONCLUSION: A significant proportion of people with CRS have symptoms of depression and anxiety, and early screening for depression and anxiety in people with CRS is critical. And, more attention needs to be given to females and patients with CRSsNP during screening. PROSPERO REGISTRATION NUMBER: CRD42022345959).

[Difficult-to-treat chronic rhinosinusitis-when the standard treatment is not effective and biologics are not available]. / Schwierig zu behandelnde chronische Rhinosinusitis ­ wenn die Standardtherapie nicht wirkt und Biologika nicht zur Verfügung stehen.

BACKGROUND: In recent years, significant improvements have been made in the treatment options for uncontrolled chronic rhinosinusitis (CRS) refractory to standard medical and surgical therapy. This is the result of a better understanding of the pathophysiology and the resulting development of biologicals for CRS with nasal polyps (CRSwNP). However, biologics are not (yet) available for all patients in Europe. OBJECTIVE: Based on the session "Difficult-to-treat CRS, when biologics are not available" at the 29th Congress of the European Rhinologic Society (ERS) 2023 in Sofia, Bulgaria, the treatment options for uncontrolled CRS with the exclusion of biologics will be discussed. MATERIALS AND METHODS: The content of the presentations "Is there a place for antibiotics?" "Indications for revision surgery," "Novel systemic treatment options," "Novel local treatment options," and "Phototherapy for nasal polyps" are outlined and supported by a review of the literature. RESULTS: Various treatment options are available for managing uncontrolled CRS, even if biologic treatments are unavailable. Treatment options for type­2 (T2) CRS include steroid rinses, repeated short-term oral steroids, steroid-eluting stents, and extended sinus surgery. In the case of nonsteroidal anti-inflammatory drug (NSAID)-exacerbated respiratory disease (NERD), acetylsalicylic acid (ASA) desensitization can be considered. Non-T2 endotypes or CRS without nasal polyps (CRSsNP) may benefit from several weeks of macrolides and xylitol rinses. CONCLUSION: To accurately assess the efficacy of second-line therapies for treatment of difficult-to-treat CRS within an endotype-specific framework, additional controlled clinical trials are needed that take into account the heterogeneity of CRS endotypes.

Eosinophil extracellular traps in eosinophilic chronic rhinosinusitis induce Charcot-Leyden crystal formation and eosinophil recruitment.

Eosinophil extracellular traps (EETs) are implicated in various eosinophil-associated diseases; however, their role in chronic rhinosinusitis (CRS) remains unclear. In the present study, 57 CRS patients were enrolled, and immunofluorescence was used to analyze EETs in eosinophilic (eCRS) and non-eosinophilic (Non-eCRS) tissues. MSD was used to examine IL-4, IL-5, and IL-13 concentrations in tissue homogenates. Charcot-Leyden crystals (CLCs) protein expression was detected in PMA, PMA+DNase I, and blank control eosinophils using ELISA. Eotaxin-3 mRNA and protein levels were measured in human nasal epithelial cells (HNECs) cultured with EETs, EETs+DNase I, DNase I, and unstimulated eosinophils using PCR and ELISA. EETs were significantly increased in eCRS tissues compared with Non-eCRS (P<0.001), and correlated with VAS and Lund-Mackay CT scores. IL-5 expression was related to EETs formation (r = 0.738, P<0.001). PMA-stimulated eosinophils exhibited higher CLCs protein levels (P<0.01). Co-culturing HNECs with EETs significantly increased eotaxin-3 mRNA and protein levels (P<0.0001, P<0.001) compared with other groups. The study suggests EETs formation is elevated in eCRS patients and is involved in CLCs formation and chemokine secretion, promoting eosinophilic inflammation.